Finding Small Roots of Multivariate Polynomials Modulo an Integer [closed]

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I am trying to apply Coppersmith's attack to find small roots of an example polynomial

$f(x,y) = (8x+7)(8y+7) \pmod{8}$

It is to my understanding that finding small roots of a multivariate polynomial modulo an integer is not implemented in Sage. However, is there a workaround code / method that will allow for small root finding of the above polynomial, and others of the same form?

Thanks, and your time and effort are greatly appreciated.